The 3GPP (third generation partnership program) is a consortium that is commissioned with the task of standardising cellular telecommunication networks.
Recently in the 3GPP consortium the long-term evolution of the UTRAN (UMTS (Universal Mobile Telecommunication System) Terrestrial Radio Access Network) has become work item that is focussed on. This UTRAN long term evolution work is known as LTE. Among the topics of the LTE work is the configuration of radio access networks for different kinds of network services and in particular the development of tailored modulation schemes for providing such kinds of services. A modulation type recently considered in LTE for the physical layer is OFDM (orthogonal frequency division multiplexing), in that orthogonal signals are synchronised and modulated on neighbouring (sub-) carriers. It is foreseen to apply this modulation scheme also for the transmission of MBMS (multimedia broadcast/multicast services).
For the provision of MBMS services it is furthermore considered to apply transmission scheme in that the same information is transmitted time synchronously using a modulation and coding scheme common for a plurality of cells within a cellular radio access network. Such a radio network comprising a plurality of cells in that a common modulation and coding scheme is applied for a synchronous transmission within the various cells is known as SFN (single frequency network). Within an SFN, a mobile station is normally located within the coverage area of more than one cell, or with other words covered by more than one eNB (evolved Node B). By this a constructive superposition of signals from neighbouring cells can be utilised to achieve a sufficient signal level at a receiving mobile station.
For the provision of an MBMS service one or a plurality of SFNs can be applied, advantageously augmented with one or more isolated cells.
The configuration of an SFN service can be either static or dynamic. In a static SFN, termed SSFN, the SFN can only be reconfigured, e.g. by adding and/or removing cells from the SFN by applying operation and maintenance commands to configure the SFN on a long term basis. Any short term user activity cannot be considered in a SSFN and any consideration of radio conditions has to be an the level of network planning.
To overcome this drawback, a more dynamic configuration of network has been proposed. However a clear concept for this has not been established yet.